Sea otters are a conservation recovery success story but continue to face threats from oil spills, entanglement, and disease. As a keystone species, their welfare has cascading effects on entire kelp forest ecosystems.
Sea otter welfare is threatened by multiple human-generated hazards including oil contamination, boat strikes, shark bites (increasingly common in California), and toxic algal blooms. Their absolute dependence on dense fur for insulation — they have no blubber layer — makes oil spill contamination rapidly fatal from hypothermia. Nutritional stress from invertebrate prey depletion causes extended foraging time that creates energy deficits. The welfare of individual sea otters is also an ecological welfare issue given their keystone role — each otter that survives to maintain urchin populations enables kelp forest recovery that supports entire communities of organisms.